The history of sales person has started during late 18th century and early of 19th century. In the initial days, salespersons were used to travel different countries. The key strategy applied was to barter and exchange as there were few selling opportunities.
During 1950s-70s, the US was overwhelmed by World War II, Americans were found to be riding on feel good factor. There fore demand for good was dramatically high. The salespersons were paid on a commission basis. On the other hand, new means of communication were incorporated to advertise and sell products or services.
However, the current economy is characterized by customer centric marketing. The present buyer has more power than ever before. Sales persons should be an expert, presentable, believable, reputable and consumable. 70% of buying decisions are made even before the entry of a sales person.